A powerful blizzard swept through Colorado on Saturday, dumping at least 2 feet (61 cm) of snow in some parts of the state and forcing the cancellation of most of the scheduled flights at the Denver airport, officials said.
United Airlines canceled all of its flights to and from Denver International Airport, the airport said in a statement.
All told, more than 800 flights were grounded on Saturday, or more than 65 percent of all scheduled take-offs and landings at the airport, the FlightAware airline tracking website showed. Dozens of other flights were delayed.
Denver International is the fourth-largest hub for United Airlines and Southwest Airlines, and the primary hub for Frontier Airlines, according to its website.
A representative for the airport did not immediately return a call or email seeking comment.
The heavy snow began falling on Friday night and was expected to continue through Sunday, the National Weather Service said.
By noon local time on Saturday, nearly 5 inches (13 cm) had fallen in Denver, Colorado's largest city, while the storm dumped up to 2 feet (61 cm) of snow in the mountains and foothills, said National Weather Service meteorologist Jim Kalina.